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Descending...throttle stick down

Discussion in 'Pro/Adv Discussion' started by druss2001, Aug 26, 2015.

  1. druss2001

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    Doing research on the Phantom 3 Advanced...but seems to pertain to any Phantom 3, probably all Phantom series...

    If I had the drone at 100' and wanted to bring it down, it would take about over 10+ seconds to bring it down with the descent speed of 3 m/s...if I held the stick down all the way...wouldn't the motors stop after 3 seconds and the drone free fall?

    Dave
     
  2. msinger

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    The motors will only stop after your Phantom stops descending for 3-5 seconds.
     
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  3. Chris Vedeler

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    No. I do this all the time. The motors only stop when it no longer detects downward movement.
     
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  4. III% Streve

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    There IS a potential for a crash in a full speed decent though. The vortex created by each prop can cause significant instability as you fly through it. The term for it has totally escaped me at the moment. This instability is easy to see, and sometimes gets pretty crazy. A little lateral movement at the same time reduces this.
     
  5. Oso

    Oso

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    I think it is called vortex ring state. It has been discussed here in the forum, and the mods have said that it is not an issue (very unlikely) with the P3 due to the orientation of the motors. They are not vertical.

    They already worked out what is too fast and what is good for safe descent and built that into the limit they set. The P3 will safely descend straight down at whatever speed you use up to the limit.

    I take them at face value and always do full down, but since you have an aviation background I'm sure that you understand much better than I do. Perhaps I'm taking too much of a risk.
     
    #5 Oso, Aug 26, 2015
    Last edited: Aug 26, 2015
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  6. Milehigh970

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    I think that's why the rate of decent is so slow.. but could be wrong. I never owned a previous model but from videos it looks like they would descend much faster. I think that's where the VRS Issues were. Again I could be completely wrong.
     
  7. bbfpv

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    Descent speed is 50% faster on the P3 than on the P2. It was brutal coming down. First time I went full throttle down on the P3 it scared me lol
     
    #7 bbfpv, Aug 26, 2015
    Last edited: Aug 26, 2015
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  8. Milehigh970

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    I stand corrected lol
     
  9. III% Streve

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    I didn't mean it to sound like you WILL crash.. just that its far more likely the faster you descend. Descending down through an up flow will significantly increase this risk. But its not very often someone will be descending down the face of a hill that is big enough to have a healthy up flow. I've BEEN in this kind of situation dropping in too quickly to drop water on a wild-fire on the side of a hill.. in a real situation.

    I was more just trying to add a bit of a disclaimer to the initial response. The last thing we need is someone to end up crashing and they come back here complaining that we told them do something that caused the crash.
     
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  10. acherman

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    That's 90% of my flight locations. haha One site I will be flying at later today actually used to have a hang glider launching platform.
     
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  11. III% Streve

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    Im in Kansas.. Not too many cliffs around here. But there are a few
     
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